text: The biosynthetic gene cluster for agglomerins is 12 kb, and codes for 7 open reading frames. The glyceryl-S-ACP is derived from D-1,3-bisphosphoglycerate by Agg2 (glyceryl-S-ACP synthase) and Agg3 (acyl carrier protein). The acyl chain is taken from primary metabolism as a 3-oxoacyl-CoA thioester. The glyceryl-S-ACP and 3-oxoacyl-CoA thioester are joined by Agg1, a FabH-like ketosynthase, forming new C-C and C-O bonds.  The primary alcohol of the intermediate 4 is then acylated by Agg4, using acetyl-CoA, before the abstraction of a proton and concomitant loss of acetate catalyzed by Agg5 to generate the exocyclic double bond.